I know Mustangs Plus sells them, but I think they're asking a bit more than I'd spend, around $1100 if I remember right. I think I'd try a PowerTrax locker before I spent that much. I know several people on this forum have used them with great results and they're only around $400.
Currie has them. I have only seen one in a junk yard in all my years of going and that one resides in my garage at the moment. I doubt you will find one for the $45 I paid at Pick-A-Part.
I got one from a member of another forum (fast500xl1) for $650 to my door with no core.
3.55 gears with traction lock. Went in like a dream. Took longer to mop out the old housing then anything else. Works like a champ..
I love my Ricmond Gear power trac locker, I never had any luck finding a stock locker for an 8", it's a bit noisy turning out of parking lots but it damn sure locks both tires up and theres no clutches to wear out. I got mine for 500.00 from summit and it was worth every penny